Technical Non starter
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Technical Non starter
The one way fuel valve, where the fuel pipe is fitted to the pump, on the high pressure pump is jammed open, tried to push the valve with a small punch, it does not return, i have a fuel pump of a fiat doblo and i can feel the valve closing, ie pushing the punch back out.
could this be the problem, valve not closing stopping the hight pressure build up in the pump
CAN some one tell me if the high pressure pump can be removed with out removing the cambelt and gear, looking at a new one it looks like the end goes into a gear, the power steering pump i think???
could this be the problem, valve not closing stopping the hight pressure build up in the pump
CAN some one tell me if the high pressure pump can be removed with out removing the cambelt and gear, looking at a new one it looks like the end goes into a gear, the power steering pump i think???
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eLearn suggests that it can be done. See link to 4cardata website. Iveco provide a clearer diagram of the pump, which may not be included in the 4cardata site, due to cropping of longer files.
Hi communicator/
In the link that's not the same pump the end of that one fits onto a gear and is driven by the cambelt.
the one i have has a long end with fine teeth at the end, which i think fits into the vacuum pump and the vacuum pump is driven by the cambelt, i think
I have looked on autodoc at the pump for my van, and as i have said the end that is driven is not the same
Thanks for all of your help, again
In the link that's not the same pump the end of that one fits onto a gear and is driven by the cambelt.
the one i have has a long end with fine teeth at the end, which i think fits into the vacuum pump and the vacuum pump is driven by the cambelt, i think
I have looked on autodoc at the pump for my van, and as i have said the end that is driven is not the same
Thanks for all of your help, again
Sorry I have come to this late, what was the original issue , was it running fine one day and not the next, or did it have a history of poor starting etc.
With the fuel system all connected correctly, on a diagnostic tool on cranking you need a minimum of around 230Bar for the ECU to instruct the injectors to open to start the engine.
Low pressure can be caused by several things, the fuel regulator on the pump it's self, one common thing can be a faulty injector which can sometimes be shown up using a leak off test measuring the fuel leaking from the return pipes on the injectors. When one fills the measuring bottles much quicker than the rest it is well worth having it checked.
I assume you have a good supply of air free fuel coming up to the high pressure pump?
Photo below should be your pump and shows the regulator. Not sure if that pump comes off easily, the 1.3, 1.6 and 2.0 litre ones are mounted at the bell housing end of the engines in most cases and are a simply dog drive.
Note on Common Rail engines one faulty injector or slack union is enough to stop the engine, unlike old school diesels.
With the fuel system all connected correctly, on a diagnostic tool on cranking you need a minimum of around 230Bar for the ECU to instruct the injectors to open to start the engine.
Low pressure can be caused by several things, the fuel regulator on the pump it's self, one common thing can be a faulty injector which can sometimes be shown up using a leak off test measuring the fuel leaking from the return pipes on the injectors. When one fills the measuring bottles much quicker than the rest it is well worth having it checked.
I assume you have a good supply of air free fuel coming up to the high pressure pump?
Photo below should be your pump and shows the regulator. Not sure if that pump comes off easily, the 1.3, 1.6 and 2.0 litre ones are mounted at the bell housing end of the engines in most cases and are a simply dog drive.
Note on Common Rail engines one faulty injector or slack union is enough to stop the engine, unlike old school diesels.
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It was parked up for 6 months, its a camper van.
Read the codes, crankshaft sensor faulty, fitted a new one, still crankshaft code. Sent ecu for repair, now no codes.
Tank fuel pump pumping fuel to high pressure pump, the spring loaded one way valve in the pipe connected to the pump is stuck open, think the spring is rusted and broke ?? so not shutting of, letting fuel run back to the low pressure pipe
Can see video on how to remove the pump, I think, looking at the autodoc pump for this van its Multi spline not a tapered end that fits into the power steering pump that is driven by the camshaft
The one you are showing looks like the one i have but i cant see the shaft side of the pump
So i still need to know can i remove it with out changing the cambelt, ie unbolt it and remove it from the rear of the housing
BUGSYMIKE, thanks for your help
Read the codes, crankshaft sensor faulty, fitted a new one, still crankshaft code. Sent ecu for repair, now no codes.
Tank fuel pump pumping fuel to high pressure pump, the spring loaded one way valve in the pipe connected to the pump is stuck open, think the spring is rusted and broke ?? so not shutting of, letting fuel run back to the low pressure pipe
Can see video on how to remove the pump, I think, looking at the autodoc pump for this van its Multi spline not a tapered end that fits into the power steering pump that is driven by the camshaft
The one you are showing looks like the one i have but i cant see the shaft side of the pump
So i still need to know can i remove it with out changing the cambelt, ie unbolt it and remove it from the rear of the housing
BUGSYMIKE, thanks for your help
Do not rely on pictures on autodoc being accurate or their part numbers.
If you want to order from autodoc you must supply your vin number to them before placing order or you will have to pay return postage for any incorrectly supplied parts.
Eper on forum is very good.
I am not aware of any one way valve in inlet to common rail hp pump. There is often a spring loaded valve the purpose of which eludes my memory currently but possibly relating to stopping pump running unlubricated.
If you want to order from autodoc you must supply your vin number to them before placing order or you will have to pay return postage for any incorrectly supplied parts.
Eper on forum is very good.
I am not aware of any one way valve in inlet to common rail hp pump. There is often a spring loaded valve the purpose of which eludes my memory currently but possibly relating to stopping pump running unlubricated.
Thanks jackwhoo, the pump shaft is to short to reach the cambelt gear, there is a 5ins spacer then a 4ins block before it gets to the cam belt i think it can be removed from the rear with out removing the belt, but i would like to see a video or conformation that it is posable
It may be worth trying to undo it and see if it will slide out as no timing points necessary on Common Rail pump. In the photo you can see there is no adjusting slots in the mounting points that secure it to housing. So if it slides out and for peace of mind nothing is moved on engine afterwards, you could mark it on removal. I suspect it will have a gear drive design from the older type pre Common Rail pumps as basically the same engine.
On the Siemens pump on a 2.0 litre Fiat Scudo (Peugeot engine RHR) I had there was a part number code sticker on the pump which, I don't know if the Bosch one will have as they usually rely on a long string of numbers.
Re my query on history of non starting, was the vehicle in normal running order when parked up, or did you acquire as a non runner?
Not sure about the valve you refer to, I believe there was a return filter on some Bosch pumps that would block and cause issues.
As I understand it the Bosch pumps use an electric primer pump in the tank which I prefer. The Siemens high pressure pump has a hand primer and uses a "suction" side of the high pressure pump which is a poor design in my eyes.
In some cases I have used a gravity feed fuel tank to locate a fault, such as air leaking into the fuel line via a poor connector, but this is more related to the Seimens design that uses vacuum and so encourages air to be drawn in. With the Bosch version using a low pressure pump in tank , then any leak would be fuel coming out so more obvious.
Re a rusted spring in a valve in fuel line allowing fuel to run back to low pressure pump, I think you will find if pressure reduced on low pressure side then the ECU would sense it and trigger the low pressure pump, much the same as when you first turn the ignition on and you here it build up line pressure.
The only thing along those lines that I can think of is a fault fuel pressure regulator on the high pressure pump it's self, which if faulty would allow fuel to join the injector leak off side of the system , returning fuel to the tank. When working correctly it is able to fine tune the exact pressure in the Common Rail that the ECU asks for.
I am sure you know this, but even a tiny leak from a poor union etc. on the Common Rail side of the high pressure pump is enough to prevent the engine from running as it requires roughly a minimum of 230Bar of pressure to activate the injectors.
This is why a good diagnostic tool giving live data when cranking the engine would show if reaching that minimum pressure or not is very useful.
Thank you for taking the time to reply back to me
I changed the high pressure regulator with one from another pump that i know works ok
The spar pump that i have has a one way cut of plunger and spring in the inlet pipe, i have removed it to have a look
I do not have a pressure tester , but as i have said no fuel comes out of the high pressure side, not even a drop
What i did see or not, there is no second o ring seal on the pressure sensor or the one from the spare pump, which was working fine on another fiat
I fitted a none return valve in the line to the low pressure side, that did no work
My next plan of attack is remove the pump,
Thanks again for all of your help
I changed the high pressure regulator with one from another pump that i know works ok
The spar pump that i have has a one way cut of plunger and spring in the inlet pipe, i have removed it to have a look
I do not have a pressure tester , but as i have said no fuel comes out of the high pressure side, not even a drop
What i did see or not, there is no second o ring seal on the pressure sensor or the one from the spare pump, which was working fine on another fiat
I fitted a none return valve in the line to the low pressure side, that did no work
My next plan of attack is remove the pump,
Thanks again for all of your help
Change the hp but make sure it is correct pump for your engine....They are not all the same , especially make sure it has the correct suction control valve(Or whatever you want to call it)
A clue problem with hp pump could be the in tank pump cannot push fuel through it when engine not turning.
Ps it is not a non return/check valve in the fuel inlet of hp pump
Pps neither electrical "things " on the hp pump are pressure sensors
A clue problem with hp pump could be the in tank pump cannot push fuel through it when engine not turning.
Ps it is not a non return/check valve in the fuel inlet of hp pump
Pps neither electrical "things " on the hp pump are pressure sensors
jackhoo, thank for the input
When the return pipe from the hp pump is removed and ignition turned on the fuel comes out with force, it sprays the rad, so its getting through the hp pump
Question, if the top and rear wires connector are removed will it still build pressure ???
Just looked a a engine for sale with the hp pump removed and the camshaft belt is still on, so that pump is coming of, unless there are more ideas
Thank again al,l for the help
When the return pipe from the hp pump is removed and ignition turned on the fuel comes out with force, it sprays the rad, so its getting through the hp pump
Question, if the top and rear wires connector are removed will it still build pressure ???
Just looked a a engine for sale with the hp pump removed and the camshaft belt is still on, so that pump is coming of, unless there are more ideas
Thank again al,l for the help
On many common rail engines , key on , in tank pump running, scan tool shows increase in rail pressure from in tank pump......so I would expect to see fuel flow through hp pump out feed pipe to fuel rail .
NO with electrical connectors removed the hp pump will NOT work at all
If your pump is the same as the one in my earlier photo, this regulator matches that number, not sure if that is your problem though as you have tried another.
Re the Common Rail Fuel pressure I didn't mean test with a mechanical gauge just a good diagnostic tool like MES or Snap On etc. using their live data section where you should see that minimum reading of 230 Bar pressure at least.
Another thing would be to do a "leak off " test which can show if a faulty injector.
Re the Common Rail Fuel pressure I didn't mean test with a mechanical gauge just a good diagnostic tool like MES or Snap On etc. using their live data section where you should see that minimum reading of 230 Bar pressure at least.
Another thing would be to do a "leak off " test which can show if a faulty injector.
